Apparatus for providing a plurality of independent control signals



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I 1 l l r l l IFI lllllllllmll l 1W L I V Mnpgllmllllmll J W I lIHIIHHHWHH o l l l I I I 64 69 1 "/IHIIIIH" L ,I INVENTOR. N1'-ALEX/w05? F www April 28, 19470 A. F. RAPlsARDA APPARATUS FOR PROVIDINGA PLURALITY OF INDEPENDENT CONTROL sIGNALs v 4 Sheets-Sheet 2 Filed Dec-5. 1967 April 28, 1970 A. F. RAPlsARDA 3,509,509

APPARATUS FOR PROVIDING A PLURALITY OF INDEPENDENT CONTROL SIGNALS FiledDSC. 5. 1967 4 Sheets-Sheet 5 April 28, 1970 A. F. RAPISARDA 3,509,509

APPARATUS FOR PROVIDING A PLURALITY 0F INDEPENDENT CONTROL SIGNALS FiledDec. 5. .1.967v 4 Sheets-Sheet 4 United States Patent O 3,509,509APPARATUS FOR PROVIDING A PLURALITY OF INDEPENDENT CONTROL SIGNALSAlexander F. Rapisarda, Mount Vernon, N.Y., assignor to Ward LeonardElectric Co., Mount Vernon, N.Y., a corporation of New York Filed Dec.5, 1967, Ser. No. 688,158 Int. Cl. H01c 5/02 U.S. Cl. 338-128 2 ClaimsABSTRACT OF THE DISCLOSURE A preset card comprises a mounting board andcover. The mounting board has spaced parallel potentiometers extendingbetween electrically conductive buses at adjacent opposite edges of themounting board. The potentiometers have movable contacts mounted on thecover for tapping a given voltage. The potentiometers comprise a wirewound resistor extending between the buses and electrically connectedthereto and rails parallel to the resistors and connected to theresistors by the movable contacts. The rails project through themounting board for contacting the terminals of a controlled apparatus.The preset card is removably mounted in a panel having individualterminals for engaging a respective rail for applying the selectedvoltage to a controlled apparatus.

BACKGROUND OF THE INVENTION In present commercial systems for dimmingtheatre lights a preset console is provided with two or morepotentiometers for a given lighting circuit. One set of potentiometersis set in advance of the scene and the lighting systems faded from thecontrolling set to the succeeding controlling set on a change of scenes.This means that the operator of the stage lights is required to set eachscene for each performance. This has the disadvantage of error beingintroduced into the presetting of the Vpotentiometers so that theplanned or programmed lighting effect is not attained due to amisadjustment of the potentiometers.

SUMMARY OF THE INVENTION An apparatus for providing a plurality ofindependent control signals, such as a preset card for setting theillumination of stage lights, comprises a mounting board withpotentiometers on one side and the terminals for the control signals onthe opposite side and a cover with movable contacts engaging arespective potentiometer for selecting the control signals appearing onthe terminals on the other side. The apparatus or preset card ismountable in a console panel for insertion and removal therefrom withthe movable contacts preset to provide the selected signals. v

An object of the invention is to provide a preset signal controlapparatus that is readily inserted and removed from a panel for applyingsignals at preset values to controlled equipment.

Another object of the invention is to provide a preset signal controlapparatus that comprises a minimum or parts and is easily assembled.

Other and further objects and advantages will be apparent from thefollowing description taken in connection with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. l is a front view of the presetcard mounted in a panel.

FIG. 2 is a partial side view of the preset card mounted in a panel andpartial sectional view taken along lines 2 2 of FIG. 1.

FIG. 3 is a sectional view of the preset card mounted in a panel takenalong lines 3-3 of FIG. 1.

FIG. 4 is a perspective view of the cover and mounting board explodedfrom the panel shown perspectively.

FIG. 5 is a front view of the mounting board.

FIG. 6 is a fragmentary perspective view of the mounting board with arail illustratively positioned forwardly from the mounting board.

FIG. 7 is an enlarged perspective fragmentary view of the cover with amovable contact separated from the cover. Y

FIG. 8 is an enlarged perspective view of the contact and supportingblock of the movable contact in a separated relation.

FIG. 9 is a fragmentary perspective rear view of the comer of the cover.

FIG. 10 is a sectional view of the mounting board taken along lines10-10 of FIG. 5.

FIG. 11 is a sectional view of a resistor of the potentiometer takenalong lines 11-11 of FIG. 10.

FIG. 12 is a front view of the terminal board.

DETAILED DESCRIPTION As best shown in FIGS. 2, 3 and 4 the preset cardcomprises a mounting board 20 and a cover 21, both made of a plasticelectrical insulating material. The mounting board has buses orelectrically conductive strips 22, 23 extending longitudinally alongopposite edges of the mounting board on the same side. Potcntiometers 24are mounted between the buses 22, 23 in a parallel relation. The cover21 is positioned over the resistors 36 and rails 40 of thepotentiometers and the movable contacts 25 (FIGS. 2 and 3) of thepotentiometers are slideably mounted in the cover and adjustably engagethe resistors 36 and rails 40 of the potentiometers. The mounting boardand cover are fastened together providing a unitary member that ismountable in a pan assembly 26 rernovably holding the preset card. Thepan assembly 26 1s secured to a panel 27. The pan assembly has aterminal board 28 (FIG. 3) with resilient contact fingers 29 forengaging the rails 40 of the potentiometers 24 (FIG. 3) to receive theselected voltage or signal and pass it to the controlled equipment (notshown) through the terminal extensions 30 (FIG. 3) of control lingers29. The terminal extensions 30 are connected to controlled equipmentsuch as theatre dimmers.

The mounting board is formed from a thin plastic sheet of insulatingmaterial and has a generally elongated rectangular shape, as shown inFIGS. 4, 5 and 6. The buses 22 and 23 are formed from electricallyconductive strips riveted to the mounting board at spaced points 33 andelectrically isolated from one another. Lugs 34 and 35 are stamped fromthe respective buses 22, 23 into U-shaped clamps for receiving the wirewound resistors 36 spanning the space between the buses. The wire woundresistors 36 (FIG. l1) comprise a solid copper core 37 withapolyethylene coating 38 electrically isolating the helically woundresistor wire 39 from the conductive core 37. The resistors arepreferably spot welded and/ or cemented with a conductive cement to thelugs 34, 35 to electrically connect the resistors to the buses 22 and23. The resistors 36 are mechanically secured to the buses by slightclosure of the U-shaped clamps. The wire 39 is of a fine gage andclosely wound to evenly divide a 24volt supply connected to the buses22, 23. The resistors are spaced parallel to one another with the rails40 positioned adjacent a respective resistor and presenting an upper atedge 41 for receiving the tapped voltage. The movable contacts 25 bridgethe resistors and rails and reect a potential proportional to theposition of the movable contacts. The rails are stamped from brass orcopper strip and extend parallel to the resistors and have a generallyrectangular cross section. The lingers 42 extend over or in front of thebus 22 and are spaced therefrom. However, a thin insulating strip 31 maybe provided on the front of bus 22 to insure that no contact is madebetween the bus 22 and lingers 42. An insulating strip 32 may beprovided on the front of bus 23. At the bus 22 end projections 43 areprovided litting into slots 44 (FIGS. 3 and 6) in the mountingjb'oard.At the other end of the rails L-shaped projections 45 extend in theplane of the rail and ft through slots 46 (FIGS. 3 and 6) in themounting board so that the L-shaped projections extend underneath theboard on the opposite side from the bus 23 to electrically isolate therails 40 from the bus 23. The rails 40 are easily positioned on themounting board by inserting the L-shaped projections 45 through theslots 46 and pivoting the rails 40 into place with the projection 43extending through the opening 44.

At one end of the mounting board the bus 23 is provided with a T-shapedterminal 47 (FIGS. 2, 4, 5 and 6) extending through the mounting boardand electrically fastened to the end of the terminal to provide acontacting surface 48 (FIG. 2) underneath the board for engaging avoltage source. At the other end of the board a terminal 49 (FIG. 5),similar in configuration to the rail 40, has an L-shaped projection 50extending through a slot 51 for engaging the other terminal of the powersource. The terminal 49 is connected to the upper bus 22 therebypermitting the energization of the resistors 36.

The cover 21 is a molded pl'asticfmember and has a front panel member55, longitudinal sides 56 and 57 and ends 58, 59 perpendicular to thepanel member 55. The sides 56 and 57 (FIG. 3) and ends 58 and 59 (FIG.2) have a recess 60 (FIGS. 2, 3 and 9) formed therein to receive themountingboard 20. Notches 61 are provided in the side 56 to receive thefingers 42 of the rails 40. Parallel partitions 62 extend between thesides 56 and 57 to form recesses or grooves 63 (FIG. 9). The partitionsextend from the panel member 55 down to the mounting board 20. Slots 64(FIGS. 1 and 11) extending parallel to the resistors 36, rails 40 and-grooves 63 are provided in the panel member 55. The movable sliderlcontacts 25 extend through the slots 64 and are slideably mounted on thepanel member 55.

The movable slider contact 25 (FIGS. 2, 3, 7 and 8) comprises asupporting block 65 with an indexing projection 66 and a positioningprojection 67. The supporting block has a rectangular configuration withthe projections 66 and 67 extending therefrom, as illustrated in thedrawings. A bolt or threaded member l68 extends through the threadedpositioning projection 67 to receive a knob 69. rI`=he projections 66and 67 fit in the slot 64 with the supporting block 65 in the groove 63(FIG. 2)..The bolt 68 extends exteriorly to the panel member 55 so thatthe knob 69 is on top of the cover 21 readily accessible for setting theposition of the movable contact and locking it in place by threadingdown against the top surface of the panel member 55. A generallyU-shaped, bifurcated beryllium-copper contact member 70 .has one legseparated into fingers 71 and 72 (FIGS. 7 and 8) for lengaging the rail40 and resistor 36, respectively. The supporting block 65 is guided inits longitudinal movement by the projections 66 and 67 so that themovable contacts linearly move in relation to the resistor 36 and therail 40. The rounded portions 71a and 72a engage the rail 40 andresistor 36 and when the movable slider contact 25 is at the low voltageend the rounded portions 71a and 72a may be spaced from the end of theresistor in order to provide a minimum voltage for application to thecontrolled equipment.

The cover has bosses 73 (FIGS. 1 and 9) for receiving screws 74 passingthrough holes and/or slots 75 (FIGS. 5 and 6) in the mounting board 20to securely clamp the mounting board and cover together. The slots 61receive the fingers 42 of the rails to limit the sidewise movement ofthe rails and hold the surface 41 facing the finger 71.

The preset card tits into the pan assembly 26 (FIGS. 2, 3 and 4) havinga bottom 76, three side walls 77 perpendicular to the bottom 76 andflanges 7S extending perpendicular to the side walls to-overlap with thepanel 27. The pan is secured to the panel 27 by fastening means passingthrough the anges 78.

Along one longitudinal edge of the pan assembly 26 the side wall 77 andthe flange 78 are omitted and the bottom wall 76 is cut away, asillustrated in FIGS. 3 and 4, to form a longitudinal opening 80 betweenthe bottom wall 76 and the panel 27. The longitudinal projection 81(FIGS. 1, 3 and 4) on the side 57 ts underneath the panel 27 to rotatethe preset card into the pan assembly. On the side 56 the longitudinalprojection 82 (FIGS. 3; 4, 7 and 9) engages the projections 83 (FIGS. 1,3 and 4) mounted on the leaf spring 84 attached to the longitudinal side77 to retain the preset card in the pan assembly until forcefullyremoved therefrom.

Underneath and attached to the pan assembly 26 is the terminal board 28.The electrically conductive fingers 29 are riveted to an insulated blockor strip (FIGS. 2, 3 and 12). Bolts 86 passing through the strip 85 arefastened to` mounting members 87 on the bottom 76 lof the pan. Thefingers 29 have V-shaped portions 291i extending into the slot 80 toengage the L-shaped portions 45 of the rails 40 (FIG. 3). Thus eachpotentiometer 24 may be connected to a respective controlled circuit.

The opening 80 is partially closed over by a longitudinally extendinginsulating strip 88 (FIGS. 3 and 4) riveted to the bottom 76 to preventshortng of the rails 40' on insertion of the preset card in the panel.

It is thus seen from the foregoing that a preset card has been describedwhich is rugged in construction and can stand abuse while providing arange 'of controlled voltages or signals which may be readily varied bysmall amounts so as to easily provide the desired illumination for stagelights. The setting of the movable contacts at the desired controlledvoltage is readily attained by loosening the knob `69, adjusting themovable contact 25 and relooking in the new position by tightening theknob 69. The parts are readily made by standard techniques and areeasily fitted together to form the assembled preset card. The partitionsin addition to separating the potentiometers also engage the exteriorsurface of the mounting board to add rigidity and strength. l

Various modifications and changes may be made in the foregoing presetcard without departing from the invention as set forth in the appendedclaims.

I claim:

1. A preset card for providing a plurality of inde-I pendent controlsignals and for being removably mounted in a pan assembly comprising amounting board, a cover, said cover having a plurality of partitionsforming a plurality of grooves, slots in said cover-between saidpartitions and extending longitudinally thereto, two buses on saidmounting board extending parallel to one another in spaced relation andcrosswise to said partitions, wound potentiometers on said mountingboard extending between said buses and between said partitions to fit insaid grooves, said cover slida'bly supporting movable contacts fittingin said grooves to engage 4respective potentiometers, means exterior tosaid cover mounted on the movable contacts for positioning and securingsaid movable contacts to provide selected control signals, saidpotentiometers comprising resistors connected across said buses andelongated rails on the same side of said mounting board as said resistorand extending longitudinally adjacent to said resistor with saidrespective movable contacts having resilient fingers slidably engagingsaid resistors and rails, said rails having portions extendingrearwardly to the opposite side of said mounting board for removablyengaging terminals connected to a control circuit in said pan assembly,means on said card for releasably engaging the pan assembly, said slotsextending parallel to said potentiometers and said partitions and saidmovable contacts having supporting blocks fitting in said grooves andhaving projections extending from said supporting block into said slotsfor guiding said blocks in linear movement in said grooves, said ngersbeing mounted on said block for electrically connecting said rail andsaid resistor, fastening means on said block extending exterior to saidcover, and a knob mounted on said fastening means for moving saidmovable contact and securing said contact in a given position.

2. The apparatus as set forth in claim 1 wherein each of said rails hasa inger and said cover has notches for receiving a respective finger tohold said rails in engageable relation with said movable contacts.

References Cited UNlTED STATES PATENTS 2,288,043 6`/l942 Stanton'338-183 2,339,721 1/1944 Wilson 338-183 2,975,389 3/1961 Karg 338-1833,307,133 2/1967 Wolff 338-183 3,341,799 9/1967 Van Benthusyen et al.338-184 3,390,366 6/1968 Izenour 338-130 3,416,120 12/1968 Klug et al338-183 LEWIS H. MYERS, Primary Examiner G. P. TOLIN, Assistant ExaminerU.S. Cl. X.R. 338-183, 194

